Device for burning of materials, especially of waste oils, oils sludges and chemical waste products difficult to burn

ABSTRACT

A device for burning difficult burnable materials having two combustion chambers connected with each other, each having a coordinated air supply wherein the second chamber has a greater volume than the first chamber.

United States Patent Peter Widdig Nr. 30. Frank St., Rodenkirchen, to Cologne, Germany Sept. 25, 1968 Jan. 5, 1 971 Inventor Apipl. No. Filed Patented DEVICE FOR BURNING OF MATERIALS, ESPECIALLY OF WASTE OILS, OILS SLUDGES AND CHEMICAL WASTE PRODUCTS DIFFICULT TO BURN 6 Claims, 7 Drawing Figs.

US. Cl. 110/7, I 10/22 Int. Cl F23g 7/00 Field of Search 1 10/7, 74,

[56] References Cited UNITED STATES PATENTS 2,967,495 I/ 1961 Haan 110/22 3,195,608 7/1965 Voorheis et aI I l0/7X FOREIGN PATENTS 1,054,610 1/I967 Great Britain I 10/7 Primary Examiner-Kenneth W. Sprague Attorney-I-Iolman, Glascock, Downing & Seebold ABSTRACT: A device for burning difficult burnable materials having two combustion chambers connected with each other, each having a coordinated air supply wherein the second chamber has a greater volume than the first chamber.

DEVICE FOR BURNING OF MATERIALS, ESPECIALLY OF WASTE OILS, OILS SLUDGES AND CHEMICAL WASTE PRODUCTS DIFFICULT T BURN The invention relates to a device for burning materials, especially waste oils, oil sludges and chemical waste products ordinarily difficult to burn.

Many experiments designed to investigate the burning of waste oils and oil sludges have been conducted. For this purpose there has been used furnaces with a rotating drum into which the waste oils were injected from the front side. There has also been proposed muffle furnaces having a first combustion chamber and a secondary combustion chamber having a separate air supply. The volume of the secondary combustion chamber is, however, smaller than that of the first combustion chamber. The pressurized air burner at the end of the combustion chamber is provided with inlets for secondary air so that further air can be drawn in by the pressurized air burner. These known oil burning devices are suited only for the burning of waste oils and oil sludges.

The invention concerns solving the problem of overcoming the disadvantages of the known devices for burning waste oils and oil sludges and to develop a device which has further advantageous properties. For the solution of this problem there is proposed a device for burning materials, especially waste oils, oil sludges and chemical waste products ordinarily difficult to burn with two combustion chambers connected with one another each having its coordinated supply of pressurized air so that the second combustion chamber has a greater volume than the first combustion chamber.

According to a further feature of the invention, the burner arranged at the front of the first combustion chamber, axially aligned therewith and supplied with pressurized air, is surrounded by spaced supply nozzles for pressurized air arranged nearly on a circular line. According to a further feature of the invention, a nozzle for the addition of material difficult to burn is arranged in the space between the burner and the air supply nozzles surrounding the same, preferably above the burner.

According to a further feature of the invention the first combustion chamber is enlarged, preferably stepwise, in the direction of the flowing gases. The second combustion chamber connected with the first combustion chamber has a greater volume than the first chamber and is arranged at an angle thereto, preferably a right angle. The supply of the combustion air into the first combustion chamber is effected axially to its longitudinal extension while the supply of the combustion air into the second combustion chamber is effected at an angle to its longitudinal extension. There is thus obtained an increased turbulence of the combustion gases. By the stepwise enlargement of the first combustion chamber there is caused not only a turbulence of the combustion gases together with the entrained particles which must still be burned but by the increased volume of the combustion chambers the gases are in a condition suitable for the further absorption of oxygen. The deflection of the combustion gases by pressurized air into the next combustion chamber causes further turbulence together with absorption of oxygen contained in the air. In the second combustion chamber, an up and down movement effected by steps in the chamber provides for a sufficient dwell period therein of the combustion gases and particles to be burned. This is particularly advantageous where the burner of the invention is arranged with a further burner for burning easily burnable liquid fuels before the vertically extending chimney flue at the end of the second combustion chamber. This burner causes a further heating and ignition of the gases and particles to be burned.

According to a further feature of the invention, in the elongated portion of the first combustion chamber there is provided in the outer wall of the second combustion chamber an opening serving as a protection against explosion. A further purpose of this opening is to render possible a-greater length of the flame in the first combustion chamber.

To obtain complete combustion and to convert CO containing gases into CO containing gases, the axially directed burner at the front side of the first combustion chamber is surrounded by several, preferably six, supply nozzles for pressurized air arranged nearly on a circular line. The pressurized air emerging from the nozzles surrounding the burner carries the flame very far so that the same obtains a great length. Besides the supply of a great amount of combustion air there is also obtained turbulence of the flame. It is particularly advantageous that the air jets according to the invention simultaneously cool the brick lining of the furnace and form a continually renewed air cushion between the flame and the lining. At the end of the first combustion chamber are provided several, preferably three, supply nozzles for pressurized air which are obliquely directed toward the joined second combustion chamber and force the combustion gases into the same. To facilitate the right-angled deflection of the combustion gases, the vertical edge at the transition point from the first combustion chamber to the second combustion chamber is preferably beveled.

In the first combustion chamber there is preferably provided an upwardly opening fill opening for materials which are difficult to burn and to be sintered such as sludges and waste products of electroplating bathes which in most cases are toxic. By the heat of the first burner in the first combustion chamber, these products are burned and sintered or slagged. They are withdrawn from the furnace in a continuous or discontinuous manner.

In the drawings there is illustrated by way of example an embodiment of the invention. The invention is, however, not limited to this embodiment and further modifications are possible within the framework of the invention.

In the drawings:

FIG. 1 is a perspective view of the burning device;

FIG. 2 is a vertical cross section through the first combustion chamber on the line IIII of FIG. 1;

FIG. 3 is a horizontal cross section through the center of both combustion chambers on the line Ill-III of FIG. 1;

FIG. 4 is a vertical cross section through the second combustion chamber with the partially illustrated chimney flue;

FIG. 5 is a view in vertical cross section through the first combustion chamber on the line V-V of FIG. 3;

FIG. 6 is a view in vertical cross section through the second combustion chamber on the line VI-VI of FIG. 4; and,

FIG. 7 is a view in vertical cross section through the second combustion'chamber on the line VII-VII of FIG. 4.

The device according to the invention consists of the first combustion chamber 10 and the joined second combustion chamber 11. According to the illustrated embodiment, the combustion chamber 10 is drum-shaped and consists of the sheet-metal shell 12 which is provided in the interior with a refractory lining 13, preferably of firebricks.

At the front side of combustion chamber 10 is arranged a burner 14 supplied by means of a pipe 15 with waste oils, oil sludges or the like which are difficult to burn. For combustion purposes, the burner is simultaneously supplied with pressurized air by means of a pipe 16. Burner 14 is surrounded by an annular supply pipe 17 from which project into the combustion chamber 10, a plurality of nozzles 18, 18a, 18b..., preferably six. The pressurized air is produced by a blower 19 and supplied by a pipe 20. From this pipe is branched a pipe 21 which leads to supply nozzles 22, 22a and 22b arranged at the end of the first combustion chamber 10 in such a manner that they are obliquely directed towards the second combustion chamber 11 as is shown in FIG. 3.

As shown in FIG. 5, combustion chamber 10 has essentially a circular cross section but a flat bottom. It may be seen from FIG. 2 that combustion chamber 10 is provided with a stepwise enlargement at about half of its length. The purpose of this enlargement is to cause turbulence of the combustion gases and of the particles to be burned as well as to increase the volume in the second part of combustion chamber 10. The gases may expand thereinenabling further absorption of the oxygen in the air.

wall 24 of the second combustion chamber 11 an opening '25,

shown particularly in FIGS. 3 and4 and also in H0. 2. Combustion chamber 11 is likewise provided with a refractory lining 13 and has an arched roof 26. At about half of its length,

the combustion chamber 11 is provided at the bottom with a step 27 which together with another step 29 (arranged before the chimney flue 28 and projecting into the combustion chamber) serve to cause a turbulence of the combustion gases in the'vertical plane in the indicateddirection of flow and therefore a longer dwell period in thecombustion chamber '11. The pattern of flow is illustrated in principle in'FlG. 4

which also shows the main direction of flow. A superimposed turbulence is caused by the obliquely directed supply nozzles 22. This pattern of flow is illustrated in principle in a horizontal plane in H6. 3. v

To obtain complete combustion, in the combustion charnber'll is provided in the range of the chimney flue 28 (illustrated only partly in FIG-l) a further burner130 to which is supplied easily burnable oil in the indicated direction of arrow by means ofa pipe 31. This easily burnable oil causes a further heating and eventual ignition of thefgases and particles difficult to burn if desired or necessary. Actuation of thebumers may be effected automatically by means of an electric control system, dependent on automatically withdrawn and continually recorded gas analyses.

By means of the nozzles 18 there is injected pressurized air in an amount of about 600 in per minute. To the nozzles 22 at the end of the first combustion chamber 10 is delivered pressurized air in an amount of about 400 m per minute while the burner 30 is supplied with combustion air in .an amount of about 180-200 m per minute through one or more nozzles 32.. This combustion air is supplied under a pressure of about l 'm water; column by means of a pipe.20a branched from pipe 20.

The temperature in the first combustion chamber 10 is in the range, l400l600C. and is adjustable by throttle flaps coordinated to the nozzles (not illustrated in the drawing).

The flame has a length of about 3.5 m.

Liquids particularly difficult to burn and materials dissolved or suspended in liquids are introduced through a nozzle 33 into the combustion chamber l-by means of a pipe 34 so that they may be heated and ignited by the heat of burner, 14. Chemical waste products which are most difficult to burn, as for example sludges from electroplating bathes, are introduced into the first half of combustion chamber by means of a funnel tube 35 in connection with a fill opening 36. By the heat in the combustion chamber l0, these products are burned and partially sintered or slagged. Toxic materials contained therein are thereby rendered harmless.

' The furnace according to the invention may be used also for the recovery of graphite contaminated by oil and acids. The contaminants are burned and the'graphiteis recovered.

The furnace according to the inventionmay also be surrounded by pipescontaining water. Such pipes may be builtin, especially in the chimney flue, for the production of hot water or hot vapor.

lclaim: r

1. A device for burning materials difficult to burn comprising two combustion chambers connected with one another, each having its own coordinated supply of pressurized air, the second combustion chamber haying a-volumeequal to or greater than the first combustion chamber, said first combustion chamber beingstepwise enlarged, in the direction of the flowing gases and said second combustion chamber being connected with said first combustion chamber and arranged at an angle thereto, .and containing means for supplying c'ombustion air into said first-combustion chamber axially to its longitudinal extension and means forv supplying combustion ,air. into said second combustion chamber at an angle to its longitudinal extension.

2. A device for burning materials difficult toburn comprising two, combustion chambers connected with one another each havingitsgown coordinated supply of pressurized air, the second combustion chamber having a volume equal to or greater that the first combustion chamber, said first combustion chamber having a circular cross section with a flat bottom and being stepwise enlarged at about half of its length and at the end ofsaidfirst combustion chamber airsupply nozzles being arranged .which operateto force the combustion gases into said second combustion chamber arranged at a right ,angle thereto and having a nearly rectangular cross section,

the bottom ofrsaid second combustion chamber being provided at about half of its length with an upwardly directed step while in the roof of said second combustion chamber. is pro- .vided an. upwardly extending chimney flue.v andfanother downwardly directed step before said flue.

3. A devicez according to claim 6 whereinbefore said up wardly extending chimney flue at the end of said second combustion chamber, there 'is provided a further burner for the combustion of easily burnable 1 liquid fuels having -a coordinated air supply nozzle.

4. A device for burning materials difficult to burn, comprising a first combustion chamber, a burner arranged at-the front side of said first combustion chamber, a plurality of spaced supply nozzles c'oaxially arranged, and surrounding said burner on the same front side of said first combustion chamber'for the introduction of pressurized air arranged substantially on a circular line. l

5. A device according to claim 4, further including a nozzle for the addition of said materials difficult to burn arranged in the space between said burner and said air supply nozzles sur-. rounding said burner. I

6. A device according to claim 4, further including a second combustion chamber connected with said first combustion 

2. A device for burning materials difficult to burn comprising two combustion chambers connected with one another each having its own coordinated supply of pressurized air, the second combustion chamber having a volume equal to or greater that the first combustion chamber, said first combustion chamber having a circular cross section with a flat bottom and being stepwise enlarged at about half of its length and at the end of said first combustion chamber air supply nozzles being arranged which operate to force the combustion gases into said second combustion chamber arranged at a right angle thereto and having a nearly rectangular cross section, the bottom of said second combustion chamber being provided at about half of its length with an upwardly directed step while in the roof of said second combustion chamber is provided an upwardly extending chimney flue and another downwardly directed step before said flue.
 3. A device according to claim 6 wherein before said upwardly extending chimney flue at the end of said second combustion chamber, there is provided a further burner for the combustion of easily burnable liquid fuels having a coordinated air supply nozzle.
 4. A device for burning materials difficult to burn, comprising a first combustion chamber, a burner arranged at the front side of said first combustion chamber, a plurality of spaced supply nozzles coaxially arranged, and surrounding said burner on the same front side of said first combustion chamber for the introduction of pressurized air arranged substantially on a circular line.
 5. A device according to claim 4, further including a nozzle for the addition of said materials difficult to burn arranged in the space between said burner and said air supply nozzles surrounding said burner.
 6. A device according to claim 4, further including a second combustion chamber connected with said first combustion chamber, a plurality of further air supply nozzles at the end of said first combustion chamber, said further air supply nozzles being obliquely directed toward said second combustion chamber. 